Marilyn, the closest I can think off is - Danke Schon Guest House & Caravan Park. they are situated between the N1 and N5 close to Winburg.
Contact Details: 051 881 9292
082 776 7768
082 460 4762
Aldam is a bit further but it has all that you are looking for. Maybe depart a bit earlier?
Winburg is quite a distance past Bloemfontein if you come from Rouxville. Why not stop at one of the resorts around Bloemfontein? From Bloemfontein 500 km should easily get you anywhere in Gauteng on a very good road. There are quite a few threads about resorts around Bloemfontein. Just use the search function.
Marilyn, 25 km north of Bloem is Riviera, 500 metres off the N1. Good security and pleasant people to deal with. Just remember to fill up in Bloem.
Don't go anywhere near Aliwal Spa it's gone to the dogs